Canon EOS 80D Instruction Manual page 251

[1 (A:B)] Firing multiple slave units in multiple groups

A
If [Firing group] is set to [1 (A:B)], group C will not fire.
The 8:1 to 1:1 to 1:8 flash ratio is equivalent to 3:1 to 1:1 to 1:3 stops (1/2-
stop increments) for the exposure level.
You can divide the slave units into
groups A and B, and change the flash
ratio to obtain the desired lighting effect.
Refer to the Speedlite's instruction
manual and set one slave unit to firing
group A and the other to firing group B.
Position the Speedlites as shown in the
B
illustration.
Set [Firing group] to [1(A:B)].
1
Set the A:B flash ratio and shoot.
2
Select [A:B fire ratio] and set the

flash ratio.
Wireless Flash PhotographyN
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